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Gary
Gary, ASE Certified Technician
Category: GMC
Satisfied Customers: 15707
Experience:  GCM master tech over 25 years
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I am working on a 1997 GMC 3500 4+4 350. The vehicle will

Customer Question

I am working on a 1997 GMC 3500 4+4 350 . The vehicle will not run without poring gas in the throttle body. The fuel pressure is 65# ***** and will run until the throttle runs dry. I had a running vehicle to switch parts with and have changed the spider injection, computer. crank sensor and new distributer, engine module ,and the battery is fully charged.
ThanksCustomer
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Submitted: 1 year ago.
Category: GMC
Expert:  Gary replied 1 year ago.

I am very sorry for the long wait

if you unplug the big fuel injector connector on top of the fuel injector then with the key ON do 8 out of the 16 terminals in the connector you unplugged show 12 volts ?

if 8 do show 12 volts then connect a test light with the test light clip to battery 12 volts and when cranking it over do the OTHER 8 blink terminal your test light bulb when cranking it over ?

Customer: replied 1 year ago.
I will test in the am and get back to ya.ron
Expert:  Gary replied 1 year ago.

sounds good

Customer: replied 1 year ago.
Gary did as you ask and had a solid light on 1/2 of the terminals and no flash on the other eight when cranking over. What does this take me to.Thanks Ron
Expert:  Gary replied 1 year ago.

if NO flashing light with the test light clip connected to 12 volts then this comes down to either a bad ignition module or bad computer

isnce it runs if you add fuel that is all that is left o cause no injector pulse so there is not fuel getting into the engine

Customer: replied 1 year ago.
I will test out these and see what i get. Thanks Ron
Expert:  Gary replied 1 year ago.

with it having spark that is all it can be

Customer: replied 1 year ago.
It does have spark thanks Gary
Expert:  Gary replied 1 year ago.

correct

that is what i said if it has spark an NO injector pulse it is the ignition module or a bad computer

Customer: replied 1 year ago.
Gary I did as u ask and replaced engine control module with another new one and a known good computer. I still have a solid light on eight of the terminals but no flash on the opposing terminals. Is it possible to have a wiring problem and where would I look?. Thanks Ron
Expert:  Gary replied 1 year ago.

was the known good computer reprogrammed to your trucks VIN number ?

another computer will not work unless its programmed to your trucks VIN number

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